A method for accurately locating faults in high-voltage frequency converter optical fiber and main control system

Abstract

The present invention discloses a method for accurately locating faults of optical fiber and main control system of high-voltage frequency converter, and belongs to the field of power electronic control. The present invention inserts a specially designed data sequence, performs binary coding on the number of the loop where the data is sent, and reads the abnormal bit of the coding to determine the position of the faulty optical fiber, thereby realizing accurate positioning of the optical fiber and main control system faults, having high detection accuracy and fast positioning speed, and greatly improving the control performance of the high-voltage frequency converter and the reliability of the system.

Description

Technical Field

[0001] The invention relates to the technical field of power electronic control, and in particular to a method for accurately locating faults of an optical fiber of a high-voltage frequency converter and a main control system. Background Art

[0002] In the field of high-voltage motor drive, high-voltage inverters have received more and more attention and applications. At present, the mainstream solution of high-voltage inverters usually adopts the power unit cascade method, where a main control system controls all power units through communication, and an equivalent multi-level structure is realized through phase shifting technology. At present, each power unit of the high-voltage inverter system uses optical fiber to communicate with the main control system, which has the problems of a large number of optical fibers, complex system connections, and many fault points; when an optical fiber fails, it is impossible to accurately locate the optical fiber problem point, which will cause the system to shut down in serious cases. Summary of the invention

[0003] To solve the above problems, the present invention proposes a method for accurately locating faults of high-voltage inverter optical fibers and main control systems. Through the accurate fault locating method, the specific fault point of the optical fiber or the main control system can be quickly located, which greatly improves the control performance of the high-voltage inverter and the reliability of the system, and effectively reduces the user's operation and maintenance costs.

[0004] To achieve the above object, the technical solution adopted by the present invention is: a method for accurately locating faults of high-voltage frequency converter optical fiber and main control system, comprising the following steps: S1, insert a specially designed data sequence before transmitting valid data. The data sequence consists of 6n+8 binary numbers, where n is a positive integer, n represents the number of unit layers contained in each loop of the ring network high-voltage inverter, and each binary number is represented by x0~x 6n+7 To express.

[0005] S2, the main control chip 1 in the main control system will binary encode the number of the loop where the data needs to be sent, and assign values ​​to x0~x3 of the data sequence, then set x4 to 1 to indicate that it is working normally, and set the rest x5~x 6n+7 Set to 0, and send the obtained data sequence to the main control chip 2 through communication.

[0006] S3, after the main control chip 2 receives the data sequence sent by the main control chip 1, if it works normally, it sets x5 in the data sequence to 1, otherwise it sets x5 to 0, and at the same time sends the updated data sequence through two optical fibers to the first power unit in the loop where the data to be sent is located.

[0007] S4, the power unit number in the loop is represented by k, where k=1, 2, ..., 3n. For the first power unit, if it receives the data sequence from the main control chip 2 through two optical fibers, it means that the two optical fibers between the main control chip 2 and the first power unit are normal. At this time, the first power unit sets x6~x7 in the data sequence to 1; if it only receives the data sequence from the main control chip 2 through the first optical fiber, it means that the first optical fiber between the main control chip 2 and the first power unit is normal, and the second optical fiber is faulty. At this time, the first power unit sets x6 in the data sequence to 1 and x7 to 0; if it only receives the data sequence from the main control chip 2 through the second optical fiber, it means that the second optical fiber between the main control chip 2 and the first power unit is normal, and the first optical fiber is faulty. At this time, the first power unit sets x6 in the data sequence to 0 and x7 to 1; at the same time, the updated data sequence is sent to the next power unit through the two optical fibers.

[0008] S5, for the kth power unit, if it receives the data sequence of the k-1th power unit through two optical fibers, it means that the two optical fibers between the kth power unit and the k-1th power unit are normal. At this time, the kth power unit replaces the x in the data sequence with 2k+4 ~x 2k+5 Set to 1; if it only receives the data sequence from the k-1th power unit through the first optical fiber, it means that the first optical fiber between the kth power unit and the k-1th power unit is normal, and the second optical fiber is faulty. At this time, the kth power unit will receive the x in the data sequence. 2k+4 Set 1, x 2k+5 =0; if it only receives the data sequence from the k-1th power unit through the second optical fiber, it means that the second optical fiber between the k-th power unit and the k-1-th power unit is normal, and the first optical fiber is faulty. At this time, the k-th power unit replaces the x in the data sequence with 2k+4 Set to 0, x 2k+5 Set to 1; at the same time, send the updated data sequence to the k+1th power unit through 2 optical fibers.

[0009] S6, after the data sequence traverses all the power units used in the current loop, the main control system receives the data sequence again. According to the last received data sequence, the optical fiber and main control system faults can be accurately located. If x4~x 6n+7 If all are 1, it means that all optical fibers and the main control system in the loop numbered i are normal, where i=8x3+4x2+2x1+x0; if x4~x 6n+7 If x is 0, it means that there is a fault in the optical fiber and the main control system in the loop numbered i. If x4 is 0, it means that there is a fault in the main control chip 1 in the main control system; if x5 is 0, it means that there is a fault in the main control chip 2 in the main control system;a If x is 0 and a is an even number, it means that the first optical fiber between the zth power unit and the z-1th power unit in the main control system is faulty; a If a is 0 and a is an odd number, it means that there is a fault in the second optical fiber between the zth power unit and the z-1th power unit in the main control system, where a=6, 7, ..., 6n+7, z=floor((a-6) / 2)+1, and floor() is a floor rounding function.

[0010] Compared with the prior art, the beneficial effects of the present invention are: high-precision and rapid fault diagnosis, improving the stability and reliability of the high-voltage inverter system in complex environments, and reducing user operation and maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 Shown is a topological diagram of a 10KV high voltage inverter system provided by the present invention; Figure 2 Shown is a diagram of the main control system provided by the present invention; Figure 3 Shown is a flow chart of the method provided by the present invention. DETAILED DESCRIPTION

[0012] The following is only a preferred embodiment of the present invention. The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can understand the present invention. It should be pointed out that for those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention defined and determined by the attached claims without departing from the principle of the present invention, all inventions and creations using the concept of the present invention are protected.

[0013] Figure 1 The figure shows the topology diagram of the high voltage inverter system provided by the present invention. Figure 1 As shown in the figure, the topology diagram of the 10KV high-voltage inverter system includes: high-voltage power grid, multi-secondary phase-shifting transformer, motor M, optical fiber, main control system, and 8 power units for each phase of A, B, and C. Each layer of power units includes one power unit A for each phase of A, B, and C. y , B y , C y , y=1, 2,…, 8.

[0014] Figure 2 The main control system diagram provided by the present invention is shown in FIG. Figure 2 As shown, the main control system includes a main control chip 1 and a main control chip 2.

[0015] Among them, the high-voltage power grid is connected to the input end of the multi-secondary phase-shifting transformer; the 24 output ends of the multi-secondary phase-shifting transformer are connected to a total of 24 power units of the three phases A, B, and C; 8 power units of each phase of the three phases A, B, and C are connected in a cascade manner, and the three-phase cascade power units are connected in a Y-connection manner, and their outputs are connected to the motor M.

[0016] Among them, the optical fiber communication includes a total of 8 rings, each ring includes two optical fiber loops, and the connection method of the first optical fiber of the first ring of optical fiber communication is: starting from the main control chip 1, passing through the A1 phase power unit, the B1 phase power unit, and the C1 phase power unit in sequence, and then returning to the main control chip 1; the connection method of the second optical fiber of the first ring of optical fiber communication is: starting from the main control chip 2, passing through the A1 phase power unit, the B1 phase power unit, and the C1 phase power unit in sequence, and then returning to the main control chip 2; the remaining rings are connected in the above manner until all loops are fully connected; the number of rings represents the number of optical fiber communication rings, and the loop represents the number of optical fiber rings.

[0017] The main control chip 1 and the main control chip 2 are any one of DSP, ARM and FPGA; the main control chip 1 and the main control chip 2 communicate with each other in a serial or parallel manner, and their data are transmitted interactively in real time.

[0018] Figure 3 The method flow chart provided by the present invention is shown as follows: Figure 3 As shown, the present invention also provides a method for accurately locating faults of high-voltage frequency converter optical fiber and main control system, which is applied to Figure 1 The high voltage inverter system topology shown in the figure includes the following steps: S1, insert a specially designed data sequence before transmitting valid data. The data sequence consists of 6n+8 binary numbers, where n is a positive integer, n represents the number of unit layers contained in each loop of the ring network high-voltage inverter, and each binary number is represented by x0~x 6n+7 To express.

[0019] S2, the main control chip 1 in the main control system will binary encode the number of the loop where the data needs to be sent, and assign values ​​to x0~x3 of the data sequence, then set x4 to 1 to indicate that it is working normally, and set the rest x5~x 6n+7 Set to 0, and send the obtained data sequence to the main control chip 2 through communication.

[0020] S3, after the main control chip 2 receives the data sequence sent by the main control chip 1, if it works normally, it sets x5 in the data sequence to 1, otherwise it sets x5 to 0, and at the same time sends the updated data sequence through two optical fibers to the first power unit in the loop where the data to be sent is located.

[0021] S4, the power unit number in the loop is represented by k, where k=1, 2, ..., 3n. For the first power unit, if it receives the data sequence from the main control chip 2 through two optical fibers, it means that the two optical fibers between the main control chip 2 and the first power unit are normal. At this time, the first power unit sets x6~x7 in the data sequence to 1; if it only receives the data sequence from the main control chip 2 through the first optical fiber, it means that the first optical fiber between the main control chip 2 and the first power unit is normal, and the second optical fiber is faulty. At this time, the first power unit sets x6 in the data sequence to 1 and x7 to 0; if it only receives the data sequence from the main control chip 2 through the second optical fiber, it means that the second optical fiber between the main control chip 2 and the first power unit is normal, and the first optical fiber is faulty. At this time, the first power unit sets x6 in the data sequence to 0 and x7 to 1; at the same time, the updated data sequence is sent to the next power unit through the two optical fibers.

[0022] S5, for the kth power unit, if it receives the data sequence of the k-1th power unit through two optical fibers, it means that the two optical fibers between the kth power unit and the k-1th power unit are normal. At this time, the kth power unit replaces the x in the data sequence with 2k+4 ~x 2k+5 Set to 1; if it only receives the data sequence from the k-1th power unit through the first optical fiber, it means that the first optical fiber between the kth power unit and the k-1th power unit is normal, and the second optical fiber is faulty. At this time, the kth power unit will receive the x in the data sequence. 2k+4 Set 1, x 2k+5 =0; if it only receives the data sequence from the k-1th power unit through the second optical fiber, it means that the second optical fiber between the k-th power unit and the k-1-th power unit is normal, and the first optical fiber is faulty. At this time, the k-th power unit replaces the x in the data sequence with 2k+4 Set to 0, x 2k+5 Set to 1; at the same time, send the updated data sequence to the k+1th power unit through 2 optical fibers.

[0023] S6, after the data sequence traverses all the power units used in the current loop, the main control system receives the data sequence again. According to the last received data sequence, the optical fiber and main control system faults can be accurately located. If x4~x 6n+7 If all are 1, it means that all optical fibers and the main control system in the loop numbered i are normal, where i=8x3+4x2+2x1+x0; if x4~x 6n+7 If x is 0, it means that there is a fault in the optical fiber and the main control system in the loop numbered i. If x4 is 0, it means that there is a fault in the main control chip 1 in the main control system; if x5 is 0, it means that there is a fault in the main control chip 2 in the main control system;a If x is 0 and a is an even number, it means that the first optical fiber between the zth power unit and the z-1th power unit in the main control system is faulty; a If a is 0 and a is an odd number, it means that there is a fault in the second optical fiber between the zth power unit and the z-1th power unit in the main control system, where a=6, 7, ..., 6n+7, z=floor((a-6) / 2)+1, and floor() is a floor rounding function.

[0024] The present invention inserts a specially designed data sequence, performs binary encoding on the number of the loop where the data is sent, and determines the position of the faulty optical fiber by reading the abnormal bits of the encoding, thereby realizing accurate positioning of the optical fiber and the main control system fault, and has high detection accuracy and fast positioning speed, which greatly improves the control performance of the high-voltage inverter and the reliability of the system.

[0025] Although the specific implementation of the invention is described in detail in conjunction with the drawings, it should not be understood as limiting the scope of protection of the patent of the present invention. Within the scope described in the claims, various modifications and variations that can be made by those skilled in the art without creative work still fall within the scope of protection of the patent of the present invention.

Claims

1. A method for accurately locating faults in high-voltage frequency converter optical fibers and main control systems, characterized in that: The following steps are involved: S1, insert a specially designed data sequence before transmitting valid data. The data sequence consists of 6n+8 binary numbers, where n is a positive integer, n represents the number of unit layers contained in each loop of the ring network high-voltage inverter, and each binary number is represented by x0~x 6n+7 To express; S2, the main control chip 1 in the main control system performs binary coding on the number of the loop where the data needs to be sent, and assigns values ​​to x0~x3 of the data sequence, then sets x4 to 1 to indicate that it is working normally, and sets the rest x5~x 6n+7 Set to 0, and send the obtained data sequence to the main control chip 2 through communication; S3, after the main control chip 2 receives the data sequence sent by the main control chip 1, if it works normally, it sets x5 in the data sequence to 1, otherwise it sets x5 to 0, and at the same time sends the updated data sequence through two optical fibers to the first power unit in the loop where the data to be sent is located; S4, the power unit number in the loop is represented by k, where k=1, 2, ..., 3n. For the first power unit, if it receives the data sequence from the main control chip 2 through two optical fibers, it means that the two optical fibers between the main control chip 2 and the first power unit are normal. At this time, the first power unit sets x6~x7 in the data sequence to 1; if it only receives the data sequence from the main control chip 2 through the first optical fiber, it means that the first optical fiber between the main control chip 2 and the first power unit is normal, and the second optical fiber is faulty. At this time, the first power unit sets x6 in the data sequence to 1 and x7 to 0; if it only receives the data sequence from the main control chip 2 through the second optical fiber, it means that the second optical fiber between the main control chip 2 and the first power unit is normal, and the first optical fiber is faulty. At this time, the first power unit sets x6 in the data sequence to 0 and x7 to 1; at the same time, the updated data sequence is sent to the next power unit through the two optical fibers; S5, for the kth power unit, if it receives the data sequence of the k-1th power unit through two optical fibers, it means that the two optical fibers between the kth power unit and the k-1th power unit are normal. At this time, the kth power unit replaces the x in the data sequence with 2k+4 ~x 2k+5 Set to 1; if it only receives the data sequence from the k-1th power unit through the first optical fiber, it means that the first optical fiber between the kth power unit and the k-1th power unit is normal, and the second optical fiber is faulty. At this time, the kth power unit will receive the x in the data sequence. 2k+4 Set 1, x 2k+5 =0; if it only receives the data sequence from the k-1th power unit through the second optical fiber, it means that the second optical fiber between the k-th power unit and the k-1-th power unit is normal, and the first optical fiber is faulty. At this time, the k-th power unit replaces the x in the data sequence with 2k+4 Set to 0, x 2k+5 Set to 1; at the same time, send the updated data sequence to the k+1th power unit through two optical fibers; S6, after the data sequence traverses all the power units used in the current loop, the main control system receives the data sequence again, and the optical fiber and main control system faults can be accurately located based on the last received data sequence. If x4~x 6n+7 If all of them are 1, it means that all optical fibers and the main control system in the loop numbered i are normal, where i=8x3+4x2+2x1+x0; if x4~x 6n+7 If x is 0, it means that there is a fault in the optical fiber and the main control system in the loop numbered i. If x4 is 0, it means that there is a fault in the main control chip 1 in the main control system; if x5 is 0, it means that there is a fault in the main control chip 2 in the main control system; a If x is 0 and a is an even number, it means that the first optical fiber between the zth power unit and the z-1th power unit in the main control system is faulty; a If a is 0 and a is an odd number, it means that there is a fault in the second optical fiber between the zth power unit and the z-1th power unit in the main control system, where a=6, 7, ..., 6n+7, z=floor((a-6) / 2)+1, and floor() is a floor rounding function.

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